Safety officials respond to a reported shooting at Lone Star College Community College near Houston on Tuesday. / ABC13.com

by Doug Stanglin, Rick Jervis and Michael Winter, USA TODAY

by Doug Stanglin, Rick Jervis and Michael Winter, USA TODAY

Three people were shot at a community college north of Houston during an argument between a student and another man Tuesday afternoon, authorities said.

The shooting occurred at Lone Star College-North Harris, 20 miles from downtown Houston, about 12:20 p.m. Witnesses reported seeing two men arguing in a small courtyard between the library and the Academic Building when one man pulled a gun and shot the student, sending dozens scurrying for cover.

The student was shot three times and is reportedly in critical condition at Ben Taub General Hospital.

The gunman also received a gunshot wound, and a maintenance worker was hit in the leg from what the Harris County sheriff's office said was "crossfire."

Carlton Berry, 22, has been charged with aggravated assault, the sheriff's office said. Spokesman Alan Bernstein said Berry remained hospitalized. No other identities were available.

Authorities had not confirmed whether only one man had a gun and fired. Witnesses told local news outlets there was one shooter, but a college spokesman initially said two men fired at each other.

KHOU-TV, citing a law enforcement source, reported that one man shot the other and then accidentally shot himself in the buttocks. Sources told the station the wounded gunman turned himself in about 2:15 p.m. at Northwest Medical Center.

A female student was hospitalized with what a sheriff's official described as "a medical condition." Earlier reports indicated that someone had suffered a possible heart attack.

At the time, about 10,000 students were on campus, one of six that serve the 90,000 students enrolled in the Lone Star College System.

The school was evacuated and closed for the rest of the day but will reopen for classes Wednesday.

"We found that the incident was not an active shooter incident but was an altercation between two individuals," Sheriff Major Armando Tello said at a news conference. "One of the individuals did have a student identification. During the altercation, there was a maintenance man that was injured and shot due to crossfire. Another individual at the scene was transported (to) the hospital for a medical reason. She had a medical condition,"

Tello said the two men in the hospital are considered "persons of interest" and are being questioned, but they have not been arrested.

"This is all still under investigation," he said.

Earlier, KHOU quoted student Brittany Mobley as saying "two dudes basically get into an altercation" and one shot the other.

The station quoted one of its campus reporters as saying one of the injured was taken from the library while apparently handcuffed to a stretcher.

"All I know he got shot three times. That's all I know," Reginald Neal told KPRC-TV. "He got shot in one of his arms, in the stomach and the leg."

Mark Zaragosa spotted two victims as he left an EMT class and stopped to help before first-responders arrived.

"The two people that I took care of had just minor injuries," he told KHOU. "One gentleman had a gunshot to the knee, and the (other) actually had an entry wound to the lower buttocks area."

Cody Harris, 20, said he was in a classroom with about six or seven other students waiting for a psychology class to start when he heard eight shots. He and other students fled.

"I was just worried about getting out," Harris said. "I called my grandmother and asked her to pick me up."

KPRC-TV quoted a student, Amanda Vasquez, as saying she heard "five or six" shots while sitting in English class. She said students quickly scrambled, hiding under desks.

An alert on the college's website called on students, faculty and staff to "take immediate shelter where you are."

Richard Carpenter, chancellor of the Lone Star College System, said the campus is a "gun-free" campus but not every student is checked to see whether they're carrying weapons.

It was the first such incident in the college's 40-year history, he said.

Less than a mile from the North Harris campus, four schools with a total of 4,600 students â?? Nimitz High School, Nimitz Ninth Grade School, Dunn Elementary School, Parker Intermediate School â?? were placed on lockdown for three hours, said Mike Keeney, a spokesman with the Aldine Independent School District. Extra security guards were dispatched to the schools.

The schools reopened around 3:30 p.m., and students were allowed to leave, Keeney said. "You never take anything like this lightly," he said.